In this talk, we will discuss a variety of applications of persistent homology. We will begin with a quick overview of some of the classic examples of applications such as sensor networks and natural imagery. Then, we will explore a number of additional applications such as brain arteries, hyperspectral imagery, dynamical systems, and biological...
Creator:
Ziegelmeier, Lori (Macalester College)
Created:
2018-08-13
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Excitons are bound electron-hole pairs, i.e., atomic-H like Bosonic quasiparticles, that determine many optical and optoelectronic properties of solid materials. Exciton formation and dissociation play decisive roles in next generation solar cells. In a conventional p-n junction solar cell, the built-in potential separates the photoexcited elect...
Creator:
Zhu, Xiaoyang (University of Minnesota, Twin Cities)
Created:
2008-11-01
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with Kourosh Shoele, Dept of Structural Engr, UCSD.Fins of bony fishes are characterized by a skeleton-reinforced membrane structure consisting of a soft collagen membrane strengthened by embedded flexible rays. Morphologically, each ray is connected to a group of muscles so that the fish can control the rotational motion of each ray ...
Creator:
Zhu, Qiang (University of California, San Diego)
Created:
2010-06-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Human Computer Interaction (HCI) researchers study not only the design of the interface but also the setting in which computing is embedded, the needs of people in various contexts, and the activities they engage in while using various forms of computing. In this talk, I will give a brief overview of the variety of research methods used in the H...
Creator:
Zhu, Haiyi (University of Minnesota, Twin Cities)
Created:
2018-03-05
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This work considers an optimal inventory control problem using a long-term average criterion. In absence of ordering, the inventory process is modeled by a one-dimensional diffusion on some interval of $(-\infty, \infty)$ with general drift and diffusion coefficients and boundary points that are consistent with the notion that demands tend to re...
Creator:
Zhu, Chao (University of Wisconsin, Milwaukee)
Created:
2018-05-07
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Classical phase field models for lipid phase separation tend to minimize the interface energy, ending up with large domains after separation. A biologically more relevant scenario is the formation of local lipid domains, centered around proteins or not, called lipid rafts, which can not be reproduced by using the classical lipid phase separation...
Creator:
Zhou, Yongcheng (Colorado State University)
Created:
2015-07-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We consider the problem of stopping a diffusion process with a payoff functional that renders the problem time inconsistent. We study stopping decisions of naive agents who reoptimize continuously in time, as well as equilibrium strategies of sophisticated agents who anticipate but lack control over their future selves' behaviors. When the state...
Creator:
Zhou, Xunyu (Columbia University)
Created:
2018-06-13
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We show that new families of accelerating and almost nondiracting beams (solutions) for Maxwell's equations can be constructed. These are complex geometrical optics (CGO) solutions to Maxwell's equations with nonlinear limiting Carleman weights. They have the form of wave packets that propagate along circular trajectories while almost pre-servin...
Creator:
Zhou, Ting (Northeastern University)
Created:
2017-04-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Cohomological ideas have recently been injected into persistent homology and have for example been used for accelerating the calculation of persistence diagrams by softwares, such as Ripser. The cup product operation which is available at cohomology level gives rise to a graded ring structure that extends the usual vector space structure and is ...
Creator:
Zhou, Ling (The Ohio State University)
Created:
2022-08-02
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Cryo-electron microscopy (EM) single particle reconstruction is an entirely general technique for 3D structure determination of macromolecular complexes. However, because the images are taken at low electron dose, it is extremely hard to visualize the individual particle with low contrast and high noise level. In this lecture, I will introduce a...
Creator:
, Zhizhen (Jane) Zhao
Created:
2019-10-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We show that there are supersonic solutions to theEuler system that are not hyperbolic in the traditionalsense. These solutions occur at the transonic region,whose characteristics may both come from the sonic line andend at the sonic line. Based on the new wave structure,we offer perspectives to construct global transonicsolutions to the Riemann...
Creator:
Zheng, Yuxi (The Pennsylvania State University)
Created:
2009-07-27
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Achieving accurate prediction of free energy using molecular dynamics simulations has been a central topic in computational biophysics in the past few decades. However, it is very challenging due to slow environment responses in biological systems. We introduce the orthogonal space sampling method to actively sample the environment responses alo...
Creator:
Zheng, Lianqing (Florida State University)
Created:
2015-07-21
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The celebrated Green-Tao theorem states that there are arbitrarily long arithmetic progressions in the primes. In this talk, I will explain the ideas of the proof and discuss our recent simplifications.One of the main ingredients in the proof is a relative Szemerédi theorem, which says that every relatively dense subset of a pseudorandom set of ...
Creator:
Zhao, Yufei (Massachusetts Institute of Technology)
Created:
2014-10-01
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The Poisson-Boltzmann (PB) equation is an effective model for the electrostatics analysis of solvated biomolecules. The nonlinearity associated with the PB equation is critical when the underlying electrostatic potential is strong, but is extremely difficult to solve numerically. Recently, we have developed several operator splitting methods to ...
Creator:
Zhao, Shan (University of Alabama)
Created:
2015-07-21
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
RIVET computes degree-Rips bifiltrations, a two-parameter version of the Vietoris Rips complex that takes the density of points into account. In a Rips complex, a simplex appears when all of its faces appear. When computing single parameter persistent homology, we can simply take the maximum time of appearance of its faces to be the time of appe...
Creator:
Zhao, Roy (University of California, Berkeley)
Created:
2018-08-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
I will talk about the random periodic solutions of random dynamical systems generated by stochastic differential equations and stochastic partial differential equations. I will start with definition and motivations of studying a random periodic solution, and discuss its connection with periodic measure. I will demonstrate that to find a random p...
Creator:
Zhao, Huaizhong (Loughborough University)
Created:
2012-10-25
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We present a direct imaging algorithm for both the location and geometry of extended targets. Our algorithm is based on a physical factorization of the response matrix of an active array. A resolution and noise level based thresholding is used for regularization. Our algorithm is extremely simple and efficient since no forward solver or iteratio...
Creator:
Zhao, Hongkai (University of California, Irvine)
Created:
2005-10-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We develop computational and experimental methods to gain insights into visual functions and psychiatric disorders. We also build deep learning models that predict human behaviors and identify people with disorders. In this talk, I will share our recent innovations on data and models, aiming at understanding and predicting visual attention in na...
Creator:
Zhao, Catherine Qi (University of Minnesota, Twin Cities)
Created:
2017-02-03
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This paper presents a novel nonlinear framework for the construction of flexible multivariate dependence structure~(i.e., copula) from existing copulas based on a straightforward "pairwise max" rule. The newly constructed max-copula has a closed form and has strong interpretability. Compared to the classical "linear symmetric" mixture copula, th...
Creator:
Zhang, Zhengjun (University of Wisconsin, Madison)
Created:
2018-02-21
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We first give a brief overview of American option pricing models and numerical methods. We treat American option models as a special class of obstacle problems. Finite element formulation is introduced together with error analysis of numerical solutions. Some interesting properties about sensitivity of the option price to the payoff function are...
Creator:
Zhang, Yongmin (NONE)
Created:
2009-02-27
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Studies on the break-up of a liquid drop or an air bubble reveal that the dynamics prior to a singularity can have several forms, ranging from universal, with no memory of the initial state, or integrable, which has a complete memory. We find that how an air bubble disconnects from an underwater nozzle is associated with an unusually rich class ...
Creator:
Zhang, Wendy W. (University of Chicago)
Created:
2008-07-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In single particle reconstruction (SPR) from cryo-electron microscopy (EM), the 3D structure of a molecule needs to be determined from its 2D projection images taken at unknown viewing directions. Zvi Kam showed already in 1980 that the autocorrelation function of the 3D molecule over the rotation group SO(3) can be estimated from 2D projection ...
Creator:
Zhang, Teng (University of Central Florida)
Created:
2016-11-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we will discuss low-complexity algorithms for solving large-scale convex optimization problems. Such algorithms include: gradient projection, proximal gradient, Iterative Shrinkage-Thresholding (ISTA), Nesterov's acceleration, and Alternating Direction Method of Multipliers (ADMM). The emphasis of the discussion will be placed on th...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2016-08-01
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we will introduce conic optimization models, in particular second-order cone programming (SOCP) and semidefinite programming (SDP). We will discuss various applications of these new optimization models. Conic duality theory will be introduced as well. Finally we will introduce the so-called central path following method for solving ...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2016-08-03
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we discuss computational issues related to low-rank tensor completion and decomposition problems. Computing the so-called CP rank of a given tensor is already notoriously difficult, let alone the completion or decomposition models where the CP-rank plays the role of a regularization function. In this talk, we introduce various matri...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2018-05-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This talk presents two parts of results related to tensor computations. The first part is on a new matricization approach, resulting in lower and upper approximations for the CP-rank. In this part, theoretical properties of the new ranks (to be called the M-ranks) will be discussed, with applications to solve the low CP-rank tensor completion pr...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2016-01-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Deep generative networks have achieved great success in high dimensional density approximation, especially for approximating the distributions of natural images and languages. In this talk, we propose to leverage their approximation capability to approximate posterior distributions in Bayesian Inverse Problems (BIPs). To train deep generative ne...
Creator:
Zhang, Pengchuan (Microsoft Research)
Created:
2018-10-22
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
A dynamic treatment regime is a sequence of decision rules, each corresponding to a decision point, that determine that next treatment based on each individual’s own available characteristics and treatment history up to that point. We show that identifying the optimal dynamic treatment regime can be recast as a sequential optimization problem ...
Creator:
Zhang, Min (University of Michigan)
Created:
2018-11-09
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Conformational searching is a core task in inverse molecularkinematics. Algorithmic improvements affecting either the speed orquality of conformational searching will have a profound impact onapplications including ligand-receptor docking, ab initio predictionof protein structure, and protein folding. In this talk, we focus on aspecific geometry...
Creator:
Zhang, Ming (University of Texas)
Created:
2007-06-01
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Meng Zhang was born in Xi’an, China in 1987. She graduated from Xi’an Polytechnic University. She and her family came to the United States on February 14, 2014.
Creator:
Zhang, Meng
Created:
2015-03-20 - 2015-06-20
Contributed By:
University of Minnesota, Immigration History Research Center
Divergence functions, as a proximity measure on a smooth manifold and often surrogate to the (symmetric) metric function, play an important role in machine learning, statistical inference, optimization, etc. This talk will review the various geometric structures induced from a divergence function defined on a manifold. Most importantly, a Rieman...
Creator:
Zhang, Jun (University of Michigan)
Created:
2013-10-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The locomotion of most fish and birds is realized by flapping wings or fins transverse to the direction of travel. Here, we study experimentally the dynamics of a wing that is flapped up and down but is free to move in the horizontal direction. In this table-top prototype experiment, we show that flapping flight occurs abruptly at a critical fla...
Creator:
Zhang, Jun (New York University)
Created:
2006-06-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In recent years Peng prososed a new notion called G-expectation, a type of nonlinear expectation motivated from dynamic risk measures with volatility uncertainty. On the other hand, a martingale under the G-expectation can be viewed as the solution to a 'linear' Second Order Backward SDEs, the main subject of the short course which will be given...
Creator:
Zhang, Jianfeng (University of Southern California)
Created:
2010-06-14
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Master equation is a powerful tool for studying McKean-Vlasov dynamics where the distribution of the state process enters the coefficients directly, with particular applications including mean field games and stochastic control problems with partial information. In this talk we propose an intrinsic notion of viscosity solution for parabolic mast...
Creator:
Zhang, Jianfeng (University of Southern California)
Created:
2018-06-13
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk, we will discuss extending the optimal gradient methods for solving convex optimization to deal with more general nonlinear, possibly nonconvex and nonsmooth, optimization problems. These algorithms will treat the nonconvex and convex optimization problems in a unified way so that they will achieve the best known complexity for solv...
Creator:
Zhang, Hongchao (Louisiana State University)
Created:
2016-01-26
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We study deterministic fluid approximation models of parallel service systems, operating under first come first served policy (FCFS), when the service time distributions may depend on both the server and the customer type. We explore the relations between fluid models and the properties of stability, resource pooling, and matching rates. We find...
Creator:
Zhang, Hanqin (National University of Singapore)
Created:
2018-05-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
